Update naming convention for environmental variables to match Env90m

[krisbego]

The get_predict_table function needs to update the input table naming convention to match Env90m observed climate data. It should be bio01_1981-2010_observed_h00v04.txt and not bio1_h00v04.txt

[mueblacker]

The file names of the elevation need to be changed as well. The downloaded files are named h20v04_elev.txt instead of elev_h20v04.txt